Ignitor

ABSTRACT

A construction for an igniter is provided that enables prevention of accidental ignition without the provision of a separate lock member. An igniter includes an igniter main body ( 2 ); an expulsion nozzle for expelling gas; a gas tank ( 6 ) for storing fuel; a valve mechanism ( 8 ) for opening and closing a gas channel between the gas tank and the expulsion nozzle; an ignition device ( 15 ) for generating an ignition discharge voltage; and an operating member ( 20 ) for performing the ignition operation. At least one of the valve mechanism ( 8 ) and the ignition device ( 15 ) are provided so as to be movable in the direction that the operating member ( 20 ) is pressed, accompanying a pressing operation of the operating member ( 20 ). Ignition is enabled by blocking the movement of the movable member from among the valve mechanism ( 8 ) and the ignition device ( 15 ) during the pressing operation of the operating member ( 20 ).

TECHNICAL FIELD

The present invention relates to an igniter also known as a “firingrod”. Particularly, the present invention relates to an ignitercomprising: an expulsion nozzle for expelling gas; a gas tank forstoring fuel therein; a gas supply path for supplying gas from the gastank to the expulsion nozzle; a valve mechanism for opening and closingthe gas supply path; an ignition device for generating an ignitiondischarge voltage; and an operating member for performing an ignitionoperation.

BACKGROUND ART

Igniters having the construction described above are convenient in thatthey can be employed to ignite gas cooking equipment by depressing theignition operating member. There is demand for locking mechanisms forthese igniters to prevent inadvertent and accidental ignition, andigniters having various types of locking mechanisms have been proposed.

For example, U.S. Pat. No. 6,168,423 discloses an igniter having aone-piece lock member provided with an elastic plate spring portion atone end thereof, the middle portion of the lock member being pivotallysupported by a main body of the igniter. In this igniter, the lockmember is operated to move to an unlocked position by pressing the endopposite the plate spring into an igniter main body with, for example, amiddle finger, where it does not interfere with the ignition operationof an operating member (operated by an index finger). Elasticdeformation of the plate spring portion enables pivotal movement of thelock member to the unlocked position, and when the middle fingerreleases the lock member, the elastic return properties of the platespring portion return the lock member to the locked position.

However, in conventional igniters such as that described above, it isnecessary to employ a finger (such as the middle finger) other than theindex finger, which operates the ignition operation member. Therefore,there is a problem from the viewpoint of operability. In addition, as asimple operation such as just pressing the lock member inward enablesrelease of the lock member, there is a problem that even small childrencan perform the ignition operation by employing both hands. On the otherhand, if the lock release operation of a lock member becomes toocomplex, there is a possibility that the ignition operation will becometroublesome, thus rendering the igniter impractical. In addition, if thestructure becomes complex, there are disadvantages from the viewpoint ofcost.

Further, in the case that a lock member is provided that necessitates anon/off operation, it is likely that the locking operation of the lockmember will be forgotten with the passage of time, which defeats thepurpose of having provided the lock member.

DISCLOSURE OF INVENTION

The present invention has been developed in view of the circumstancesdescribed above. It is the object of the present invention to provide anigniter that is capable of preventing inadvertent ignition withoutproviding a lock member, that is, while obviating a locking operation.

The igniter of the present invention comprises:

an igniter main body;

an expulsion nozzle for expelling gas;

a gas tank for storing fuel therein;

a gas supply path for supplying gas from the gas tank to the expulsionnozzle;

a valve mechanism for opening and closing the gas supply path;

an ignition device for generating an ignition discharge voltage; and

an operating member for performing an ignition operation; wherein

at least one of the valve mechanism and the ignition device is providedin the igniter so as to be movable in the direction that the operatingmember is pressed, accompanying a pressing operation of the operatingmember; and

ignition is made possible by blocking the movement of the movablemember, from among the valve mechanism and the ignition device, duringthe pressing operation of the operating member.

That is, the igniter of the present invention includes those in whichonly the valve mechanism is movable, those in which only the ignitiondevice is movable, and those in which both the valve mechanism and theignition device are movable. The construction precludes ignition if atleast one of the valve mechanism and the ignition device movesaccompanying a pressing operation of the operating member.

In the case that at least the valve mechanism is movably provided, it ispreferable that:

the gas tank is provided in the igniter main body so as to be integrallymovable with the valve mechanism; and

the igniter has an opening for a rear portion of the gas tank toprotrude rearward therethrough; wherein

blocking of the movement of the valve mechanism is performed by blockingthe protrusion of the rear portion of the gas tank through the opening.

In addition, it is preferable that:

a cover for covering the rear portion of the gas tank that protrudesfrom the opening is provided at the rear end of the igniter main body soas to be slidable in the front/rear direction; wherein

the blocking of the protrusion of the rear portion of the gas tank isperformed by the cover blocking the movement of the gas tank.

A spring for returning the valve mechanism and the operating member totheir original positions may provided between the rear portion of thegas tank and the cover, as necessary.

According to the present invention, at least one of the valve mechanismand the ignition device are provided in the igniter main body so as tobe movable in the direction that the operating member is pressed,accompanying a pressing operation of the operating member. Theconstruction precludes ignition unless this movement is blocked.Therefore, inadvertent ignition can be prevented without providing alock mechanism for the operating member, as had been done inconventional igniters of this type.

A construction may be adopted wherein the gas tank is provided so as tobe integrally movable with the valve mechanism, and the blocking of themovement of the valve mechanism is accomplished by blocking theprotrusion of the rear portion of the gas tank through the opening ofthe igniter main body. In this case, blocking the protrusion of the rearportion of the gas tank through the opening and the pressing operationof the operating member can be performed simultaneously with one hand.Superior operability is also obtained, as the need to release a lockmechanism during an ignition operation is obviated. This simultaneousoperation is impossible to be performed by a small child having smallhands. Therefore, accidental ignition being performed by small childrencan be prevented.

In addition, no On/Off lock mechanism, such as those found onconventional igniters, is provided. Therefore, there is no possibilitythat a user will forget to set the lock mechanism, therefore improvingthe safety of the igniter.

Further, the operability 6 f the igniter can be further improved in thecase that the spring for returning the valve mechanism and the operatingmember to their original positions is provided between the rear portionof the gas tank and the movable cover.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional view of the main parts of an igniter according tothe first embodiment of the present invention, in an initial state.

FIG. 2 is a sectional view of the main parts of the igniter of FIG. 1,in a state in which ignition is precluded.

FIG. 3 is a sectional view of the main parts of the igniter of FIG. 1,during an ignition operation.

FIG. 4 is a sectional view of the main parts of an igniter according tothe second embodiment of the present invention, in an initial state.

FIG. 5 is a sectional view of the main parts of the igniter of FIG. 4,in a state in which ignition is precluded.

FIG. 6 is a sectional view of the main parts of an igniter according tothe third embodiment of the present invention, in an initial state.

FIG. 7 is a sectional view of the main parts of the igniter of FIG. 6,in a state in which ignition is possible.

BEST MODE OF CARRYING OUT THE INVENTION

Embodiments of the present invention will be described hereinbelow, withreference to the drawings.

FIG. 1 through FIG. 3 show sectional views of an igniter 1 according toa first embodiment of the present invention. FIG. 1 shows the igniter 1in an initial state. FIG. 2 shows the igniter 1 in a state in whichignition is precluded. FIG. 3 shows the igniter 1 during an ignitionoperation. Note that the leftward direction in the figures is designatedas “front”, and the rightward direction in the figures is designated as“rear”.

The igniter 1 is provided with an igniter main body 2 which comprises:an intermediate case 4 which is halved by the plane of the drawingsheet; an ignition portion 3 in the form of an elongate rod, integrallyprovided with the intermediate case 4 and having an expulsion nozzle forexpelling gas at the tip thereof (the tip is omitted from the figure);and a cylindrical rear case 5 having open front and rear ends, removablyattached to the rear portion of the intermediate case 4 by spigot andsocket engagement. The intermediate case 4 and the rear case 5constitute a grip portion.

A gas supply unit 7, which is slidable in the front to rear direction,is contained within the rear case 5. The gas supply unit 7 comprises: agas tank 6 equipped with a gas chamber 6 a that contains high pressuregas such as butane; and a valve mechanism 8 provided at the upperportion of the front wall of the gas tank 6. The valve mechanism 8serves to open and close a gas channel that communicates the gas chamber6 a with the expulsion nozzle. A nozzle member 10 that functions as avalve is provided within the gas channel. The nozzle member 10 closesthe gas channel by being urged rearward by a spring provided within thevalve mechanism. One end of a rotating lever 14 is engaged with the tipof the nozzle member 10. The rotating lever 14 is rotated by a pressingoperation of an operating member 20, to be described later, therebyadvancing the nozzle member 10. In this manner, the gas channel isopened to enable supply of gas to the expulsion nozzle (not shown)through the nozzle member 10.

A connector member 16 which is connected to a gas pipe 18 is fixedlyprovided in the intermediate case 4 at a position along a line extendingfrom the tip of the nozzle member 10. The gas pipe 18 extends to the tipof the ignition portion 3, and is connected to the expulsion nozzle.Note that the amount of gas supplied, that is, the size of a flame, isadjusted by a flame adjustment knob 13 that protrudes to the exteriorand is connected to an adjustment sleeve 12.

In the initial state shown in FIG. 1, a rear portion 6 c of the gas tank6 protrudes slightly rearward through the opening at the rear end of therear case 5. A movable cover 9 for covering the protruding rear portion6 c is attached on the rear end of the rear case 5 so as to be slidableforward and rearward. The movable cover 9 comprises a flat rear wall 9 athat contacts the rear end of the gas tank 6; and a cylindricalperipheral wall 9 b which is elastically engaged with the outerperipheral surface of the rear case 5. Disengagement of the movablecover 9 from the rear case 5 in a normal state is prevented by annularridges 9 c and 5 a being formed at the front end of the inner peripheralsurface of the peripheral wall 9 b and the rear end the outer peripheralsurface of the rear case 5, respectively. The movable cover 9 isattached on the rear case 5 so that it is movable between a frontposition, at which it contacts the rear end of the gas tank 6 in theinitial state shown in FIG. 1, and a rear position, to which it has beenpushed by the rear portion 6 c of the gas tank 6, shown in FIG. 2.

A piezoelectric unit 15 is provided beneath the valve mechanism 8. Thepiezoelectric unit 15 is an example of an ignition device that generatesa discharge voltage for ignition. The piezoelectric unit 15 comprises anelongate cylindrical piezoelectric unit main body 15 a having a spring(not shown) therein; and a slide portion 15 b which is urged to protrudeforward by the spring. A recess 6 b, for housing the rear portion of thepiezoelectric unit main body 15 a, is formed in the front wall of thegas tank 6 beneath the valve mechanism 8. The piezoelectric unit mainbody 15 a is fitted within the recess 6 b by being inserted thereintofrom the front. The rear end surface of the piezoelectric unit main body15 a abuts a vertical rear wall of the recess 6 b. This abutment causesthe gas supply unit 7 to move rearward integrally with the piezoelectricunit main body 15 a, and causes the piezoelectric unit main body 15 a tomove forward integrally with the gas supply unit 7.

A lead wire 23 which is connected to a first pole of the piezoelectricunit is connected to a discharge electrode (not shown). A second pole ofthe piezoelectric unit 15 is connected to the expulsion nozzle at thetip of the ignition portion 3, via a path not shown in the figures.

An ignition operation member 20 that slides in the front to reardirection is provided in the intermediate case 4, which constitutes agrip portion along with the rear case 5. The operating member 20comprises: a box-like base portion 20 b which is slidably supportedwithin the intermediate case 4; and an operating portion 20 a providedat the front end of the box-like base portion 20 b. The slide portion 15b of the piezoelectric unit 15 is engaged from behind to the upperportion of the box-like base portion 20 b, above an intermediate wall 20c provided therein. In addition, a leg portion 20 d that extendsrearward is connected to the end of the box-like base portion 20 b. Theleg portion 20 d engages with an end of the rotating lever 14 during anignition operation of the operation member 20, and functions to rotatethe rotating lever 14.

The rotating lever 14 is substantially L-shaped, and is supported so asto be rotatable about a pivot at its midpoint. In the case that therotating lever 14 is rotated counterclockwise by the leg portion 20 d ofthe operating member 20, the rotating lever 14 pulls the nozzle member10 forward to open the gas channel. At the same time, the nozzle member10 is connected to the connector member 16, thereby gas is supplied tothe gas pipe 18 via the connector member 16.

Next, the operation of the igniter 1 constructed in the above mannerwill be described.

First, the grip portion is held by one hand and the operating member 20is pressed by a finger from the initial state shown in FIG. 1. At thistime, no force is applied to the rear wall 9 a of the movable cover 9 topress it forward. That is, the gas supply unit 7 and the piezoelectricunit 15 are allowed to move rearward in this state. In this case, theforce applied to the slide portion 15 b of the piezoelectric unit 15 bythe operating member 20 does not compress the spring (in this case, thespring acts as a rigid body), but is transferred directly to thepiezoelectric unit main body 15 a. Thereby, the entire ignition device15 is pressed rearward along with the gas supply unit 7 by the operatingmember 20. The igniter 1 assumes the state shown in FIG. 2, wherein therear portion 6 c of the gas tank 6 protrudes further from the rear endof the rear case 5. Therefore, regardless of the fact that a pressingoperation of the operating member 20 has been performed, a dischargevoltage generation operation is not performed by the piezoelectric unit15.

As clearly shown in FIG. 2, the valve mechanism 8 moves rearward alongwith the nozzle member 10, accompanying the rearward motion of the gassupply unit 7 caused by the pressing operation of the operating member20. Therefore, the relative positions of the operating member 20 and thenozzle member 10 do not change from the state shown in FIG. 1. Therotating lever 14 is not rotated, and accordingly, the gas channel ofthe valve mechanism 8 remains closed. The gas supply unit 7, thepiezoelectric unit 15, and the operating member 20 are returned to theinitial state shown in FIG. 1 by releasing the operating member 20 whilepressing the rear wall 9 a of the movable cover forward.

On the other hand, the grip portion may be held while the rear wall 9 aof the movable cover 9 is engaged with the base portion of a thumb. Thatis, rearward motion of the gas supply unit 7 and the piezoelectric unitmain body 15 a are blocked. In the case that a pressing operation of theoperating member 20 is performed in this state, the leg portion 20 d ofthe operating member 20 engages the end of the rotating lever 14 torotate the rotating lever 14 counterclockwise, as shown in FIG. 3.Thereby, the nozzle member 10 of the valve mechanism 8 is pulled forwardto open the gas channel of the valve mechanism 8. Gas is supplied to thegas pipe 18 via the connector member 16, and gas is expelled from theexpulsion nozzle at the tip of the ignition portion 3.

At the same time, the slide portion 15 b of the piezoelectric unit 15enters the piezoelectric unit main body 15 a while compressing thespring housed therein. Thereby, a discharge voltage is generated,ignition sparks are generated at the expulsion nozzle, and a gas flameis generated.

As is clear from the description above, in the present embodiment, thegas tank 6; the gas supply unit 7, which has the valve mechanism 8 foropening and closing the gas channel from the gas tank; and thepiezoelectric unit 15, comprising the piezoelectric unit main body 15 aand a slide portion 15 b, which is urged forward by the spring withinthe piezoelectric unit main body 15 a are provided in the igniter mainbody 2 so as to be movable in the direction that the operating member 20is pressed, accompanying the pressing operation of the operating member20. Therefore, ignition is precluded by the piezoelectric unit main body15 a and the gas supply unit 7 moving rearward accompanying the pressingoperation of the operating member 20, unless the rear wall 9 a of themovable cover 9 is engaged to block movement thereof.

Ignition is made possible by pressing the operating member 20 whileholding the grip portion and pressing the rear wall 9 a of the movablecover 9 to block the movement of the gas supply unit 7 within theigniter main body 2. This operation simultaneously enables the openingoperation of the valve mechanism 8 and the entrance of the slide unit 15b into the piezoelectric unit main body 15 a.

In the present embodiment, the blocking of the movement of the gassupply unit 7 and the piezoelectric unit main body 15 a is performed byblocking the movement of the movable cover 9. This construction allows auser to block the movement of the gas supply unit 7 and thepiezoelectric unit main body 15 a while performing the pressingoperation of the operating member 20 using only one hand. Therefore,superior operability is exhibited by the igniter 1.

Simultaneous pressing of the rear wall 9 a of the movable cover 9 and ofthe operating member 20 with one hand is impossible to be performed by asmall child having small hands. Therefore, accidental ignition by smallchildren can be prevented.

As the igniter 1 is not equipped with a conventional On/Off type lockmechanism, the trouble of releasing the lock when performing theignition operation is obviated. In addition, there is no possibilitythat setting of the lock mechanism will be forgotten. Note that abattery may be employed instead of the piezoelectric unit 15, as theignition device.

Next, an igniter according to the second embodiment of the presentinvention will be described with reference to FIG. 4 and FIG. 5. FIG. 4is a sectional view of the main parts of the igniter according to thesecond embodiment in an initial state, corresponding to FIG. 1. FIG. 5is a sectional view of the main parts of the igniter according to thesecond embodiment in a state that ignition is precluded, correspondingto FIG. 2. Note that parts shown in FIG. 4 and FIG. 5 that correspond tothe same parts shown in FIG. 1 and FIG. 2 are denoted with the samereference numerals, and redundant descriptions are omitted.

In the first embodiment described above, both the gas supply unit,comprising the gas tank 6 and the valve mechanism 8, and thepiezoelectric unit 15 were movably provided in the igniter main body 2.However, in the igniter according to the second embodiment, thepiezoelectric unit 15 is fixed to the igniter main body 2. Only the gassupply unit 7 moves rearward accompanying a pressing operation of theoperating member 20, so that an opening operation of the nozzle member10 is not performed, as shown in FIG. 5.

Accordingly, ignition sparks are generated when the operating member 20is pressed. However, as gas is not supplied to the expulsion nozzle,accidental ignition by small children can be prevented in the samemanner as in the first embodiment described above.

Note that as a modification of the second embodiment, a construction maybe adopted wherein the gas supply unit 7 is fixed in the igniter mainbody 2. In an igniter having such a construction, ignition is precludedby only the piezoelectric unit 15 moving rearward accompanying apressing operation of the operating member 20. In this case, it ispreferable that a mechanism, for stopping the supply of gas to theexpulsion nozzle, be added.

Next, an igniter according to the third embodiment of the presentinvention will be described with reference to FIG. 6 and FIG. 7. FIG. 6is a sectional view of the igniter according to the third embodiment inan initial state. FIG. 7 is a sectional view of the igniter according tothe third embodiment in a state in which ignition is possible. Theigniter of the third embodiment is the igniter of the first embodiment,shown in FIG. 1 through FIG. 3, with an automatic return mechanism addedthereto.

In the construction shown in FIG. 6, a cup-shaped movable cover 29 forcovering the rear portion 6 c of the gas tank 6 is provided at the rearend of the rear case 5 so that it is slidable forward and rearward. Aforwardly protruding protrusion 29 d is provided at the center of thefront surface of a rear wall 29 a of the movable cover 29. A coil spring25 is provided between the rear wall 29 a of the movable cover 29 andthe rear end surface of the gas tank 6. The coil spring 25 is supportedat one end thereof by the protrusion 29 d. In this case, the length of aperipheral wall 29 b of the movable cover 29 is formed to be longer inthe front to rear direction than the movable cover 9 shown in FIG. 1, byan amount equal to the distance that the protrusion 29 d protrudes.

Annular ridges 29 c and 5 a are formed at the front end of the innerperipheral surface of the peripheral wall 29 b and the rear end theouter peripheral surface of the rear case 5, respectively. The movablecover 29 is held at a rearward position, at which the annular ridges 29c and 5 a engage each other, by the urging force of the coil spring 25.

The urging force of the coil spring 25 is set to be weaker than that ofthe spring provided within the piezoelectric unit main body 15 a.Accordingly, the gas supply unit 7 and the piezoelectric unit 15 arecapable of moving rearward until the rear end portion 6 c of the gastank 6 abuts the front end surface of the protrusion 29 d of the movablecover 29, by a pressing operation of the operating member 20 from thisstate. That is, rearward movement is possible to the same position shownin FIG. 2, by compressing the coil spring 25, thereby precludingignition. When the operating member 20 is released, the gas supply unit7, the piezoelectric unit 15 and the operating member 20 areautomatically returned to their initial positions by the urging force ofthe coil spring 25.

On the other hand, the rear wall 29 a of the movable cover 29 may bepressed forward during the pressing operation of the operating member20. If the operating member 20 is pressed while rearward movement of thegas supply unit and the piezoelectric unit 15 are blocked, by theprotrusion 29 d of the movable cover 29 abutting the rear end surface ofthe gas tank 6 as shown in FIG. 7, the ignition operation is enabled inthe same manner as that shown in FIG. 3.

According to the present embodiment, the coil spring 25 is providedbetween the rear wall 29 a of the movable cover 29 and the rear endsurface of the gas tank 6. Therefore, the gas supply unit 7 and thepiezoelectric unit 15 are enabled to be automatically returned to theirinitial positions after being moved rearward. The operability of theigniter according to the third embodiment is improved from that of theigniter according to the first embodiment in this point. Note thatalthough a coil spring 25 is employed in the third embodiment, thespring is not limited to this. It is possible to employ springs havingalternate structures. In addition, the rear walls 9 a and 29 a of themovable covers 9 and 29 are pressed to block the rearward movement ofthe gas supply unit 7 and the piezoelectric unit main body 15 a in theembodiments described above. However, the present invention is notlimited to this construction, and it goes without saying that otherengagement means are capable of achieving the objective of the presentinvention.

1. An igniter comprising: an igniter main body; an expulsion nozzle forexpelling gas; a gas tank for storing fuel therein; a gas supply pathfor supplying gas from the gas tank to the expulsion nozzle; a valvemechanism for opening and closing the gas supply path; an ignitiondevice for generating an ignition discharge voltage; and an operatingmember for performing an ignition operation; wherein at least one of thevalve mechanism and the ignition device is provided in the igniter so asto be movable in the direction that the operating member is pressed,accompanying a pressing operation of the operating member; and ignitionis made possible by blocking the movement of the movable member, fromamong the valve mechanism and the ignition device, during the pressingoperation of the operating member.
 2. An igniter as defined in claim 1,wherein the gas tank is provided in the igniter main body so as to beintegrally movable with the valve mechanism; and the igniter has anopening for a rear portion of the gas tank to protrude rearwardtherethrough; wherein blocking of the movement of the valve mechanism isperformed by blocking the protrusion of the rear portion of the gas tankthrough the opening.
 3. An igniter as defined in claim 2, wherein acover for covering the rear portion of the gas tank that protrudes fromthe opening is provided at the rear end of the igniter main body so asto be slidable in the front/rear direction; wherein the blocking of theprotrusion of the rear portion of the gas tank is performed by the coverblocking the movement of the gas tank.
 4. An igniter as defined in claim3, wherein a spring for returning the valve mechanism and the operatingmember to their original positions is provided between the rear portionof the gas tank and the cover.